“Describe” actually literally means something like “draw a circle around.” That’s why, in geometry, you don’t draw a circle, you describe one. I want to play a kind of a game in which we use the word “describe” very literally – so, when we talk about “describing an idea” or “describing a person”, we have to find a way to say it as actually drawing a circle around something. And the attendant implications of that circle are that it is both real and arbitrary at the same time.
If you think of a piece of paper, and on a piece of paper there are a bunch of dots, and some dots are red, and some are blue, and some are green. You could draw a circle (here “circle” is being defined very loosely) around only the red dots, and then you could say, “look, there’s a red object on the page!” Is that true? Well, yes, kind of. I mean, there are red dots on the page, those are real. And the circle is certainly real, you just drew it. There is, in that respect, definitely a red object there. But at the same time, you could have also drawn a circle around all the blue dots, and made a blue object – so, we could say that there’s one real object (the red one), and two more potential objects – the blue one and the green one, since those dots are still there, they’re just waiting for you to draw a circle. But really there’s more than that, because you could have drawn a circle that included one blue dot for every red one and said there’s a purple object, or a circle that included all the dots and said “here’s an object I call ‘dots’”, and those would be equally real.
Real in the sense that they exist; arbitrary in the sense that you could just as easily have drawn a circle around something else.
So, the first step is imagining some nonsense.